Fold apparatus and method



March 6, 1962 M. LADENBURGER 3,024,019

FOLD APPARATUS AND METHOD Filed Feb. 5, 1959 3 Sheets-Sheet 1 lay/d 4- M75 m: as 32% 3,024,019 FOLD APPARATUS AND METHOD Max Ladenburger, St. Louis, Mo., assignor to Western Supplies Company, St. Louis, Mo., a corporation of Missouri Filed Feb. 5, 1959, Ser. No. 791,341 13 Claims. (Cl. 270-61) This invention relates to a folding apparatus and method, and more particularly to a positively actuated folding apparatus and method having two steps, these being a creasing step and a folding step.

The drawings indicate a preferred embodiment of the invention which may be briefly described. With the apparatus, one may fold the edge or margin of a piece of material over upon itself or upon an inner piece of material. In a typical use, one of two pieces of material is of uniformly larger size than the other piece, and is folded over the other all around the margin, so that a border is provided on the former.

The apparatus includes a mold or die here comprising the stationary part, and a plunger here comprising the movable part.

The die includes a base having a top surface in which there is formed a cavity of approximately the shape of the smaller inner work piece. Within this cavity there is a vertically depressible platform spring-urged upwardly, so as to be flush with the top of the base. A gauge having an edge shaped to receive the outer and larger work piece and position it with respect to the platform is mounted on the top of the base. Over the top of the base, another gauge plate is hingedly mounted so that it can swing over or away from the cavity. Above the cavity the gauge plate has an opening in it that provides an edge against which the smaller work piece may be disposed and positioned. By this arrangement, when the gauge plate is swung away from the base, the larger work piece can be located on the base over the depressible platform. Then when the swinging gauge plate is swung again over the cavity, the smaller work piece can be positioned on top of the larger one in such wise as to provide an even margin of the larger one around the smaller work piece.

The plunger includes a compound plunger device having an inside and an outside depressible plunger element. In the initial operation, the inside plunger element is caused to move downwardly, depressing the two work pieces and the platform, and bending up the margin of the outer work piece where the folding it to occur. The platform locks in a lowered position so that the work is retained in the cavity surrounding the platform, with its edges turned up. Thereupon the plunger is withdrawn completely, the top gauge plate is swung away from the base plate, and the plunger member is again depressed. At this time the inner and outer plunger elements descend together. The outer plunger elements are beveled so that they slide down the walls of the cavity with a knifelike edge that engages in behind the upstanding margins of the work and turns those margins inwardly, so that they overlie the remainder of the work. The inner plunger then descends on top of the margins and forces them tightly down to overlie the work where they may be cemented in position.

A more detailed description to follow will facilitate a better understanding of the invention of which the accompanying drawings illustrate only one embodiment thereof.

In the drawings:

FIGURE 1 is a plan view of the press embodied by this invention;

FIGURE 2 is a bottom view of the press;

FIGURE 3 is a side elevation of the press;

FIGURE 4 is a view in section of the press taken along the line 4-4 of FIGURE 1;

FIGURE 5 is a view in section of the press taken along the line 55 of FIGURE 1;

FIGURE 6 is a plan view of the mold shown with the top plate in the operational position;

FIGURE 7 is a plain view similar to FIGURE 6, but with the top plate in the nonoperational position;

FIGURE 8 is a side elevation of the mold with the top plate shown in the nonoperational position;

FIGURE 9 is a back view of the mold with the top plate shown in the operational position;

FIGURE 10 is a view in section of the mold taken along the line 1010 of FIGURE 6;

FIGURE 11 is a view in section of the press taken along the line 1111 of FIGURE 2;

FIGURE 12 is a plan view of the smaller piece upon which the operation is to be performed;

FIGURE 13 is a plan view of the larger piece upon which the operation embodied by this invention is to be performed;

FIGURE 14 shows the end product of two pieces folded and pressed together;

FIGURE 15 is a partial view in section showing details of the press at the instance of initial application to the mold for a folding step in the operation;

FIGURE 16 is a view smaller to FIGURE 15 but with the press at the completion of the folding step;

FIGURE 17 is a view in partial section showing the two pieces of material in creased condition;

FIGURE 18 shows a partial view in section showing the application of the press to the mold for the folding step;

FIGURE 19 is a front elevation of the press and mold at the beginning of an operation;

FIGURE 20 is a view in section taken along the line 2020 of FIGURE 19;

FIGURE 21 is a view in section taken along the lines 2121 of FIGURE 20;

FIGURE 22 is a view similar to FIGURE 20 but with the press shown performing the creasing step;

FIGURE 23 is a partial view in section similar to FIGURE 21 but showing the platform latching means in a latching condition; and

FIGURE 24 is a view similar to FIGURE 20 but showing the press underlying a folding Step in the operation.

Turning now to the more detailed description of the invention, a plunger assembly, designated generally as 30, may include a support plate 31. The support plate 31, besides supporting the plungers in a manner to be described, transmits a force to said press mechanism from a source which is not shown, such as a press, such as found in a shoe factory, and which does not constitute a part of this invention.

The support plate 31 may be provided with projecting pins 32, notched at 33, as one of the well known means of attachment to said source of force as to the ram of the press. A dowel 34 may serve as a guide and balance means when the press assembly 30 is mounted for operation upon the press. Thus, to be mounted, the plunger assembly 30 may be guided so that projections 32 will be removably locked at notches 33 to the press in a well known manner.

Projecting from adjacent corners of the support plate 31 are two dowels 35. Opposite the dowels 35, at the center of the front edge of the support plate 31 is a similar dowel 36. The two dowels 35 will form an isosceles triangle with the dowel 36 at the apex.

Also projecting from the support plate 31 are a plurality of dowels 37, 38, 39, 40, 41 and 42. The dowels 37 through 42 that vary in diameter for a convenience which will appear, are all of the same length. To facilitate attachment of the dowels 35 through 42 to the support plate 31, the dowels are reduced in diameter where necessary as at 43 through 49, peened over as at 50 through 56, and the top surface polished to form a level surface with the support plate 31 as in conventional riveting processes. Alternately, the dowels 35 through 42 may be screwed or otherwise attached to the support plate 31 by a conventional manner.

A creasing block 57 is attached to the dowels 37 through 42 by appropriately sized screws 58, 59, 60, 61, 62 and 63. The creasing block 57 may be of any desired shape depending upon the shape of the finished product. In the embodiment illustrated, the creasing block is of the general configuration of the smaller Work piece shown in FIGURE 12. Inasmuch as the dowels 37 through 42 are all of the same length, the creasing block 57, when attached to the dowels 37 through 42, will be suspended substantially parallel to the support plate 31.

A pressure plate 66 has a width substantially equal to the width of the support plate 31. Three holes, 67, 67 and 68 are so sized and placed on the plate 66 as to correspond to the diameter and position of the three dowels 35, 35 and 36. Therefore, the pressure plate 66 may be placed with the holes 67, 67 and 68 in slidable circumscription of the dowels 35 and 36.

Mounted upon the pressure plate 66 and projecting downwardly therefrom is a blade member 70. The blade member 70 is flanged to provide a vertical wall 71 having an inner surface 72 and an outer surface 73. As shown in the various sectional views showing the blade member 70, that member has an inverted square cornered U-shape. Viewed from the bottom, the blade member 70 appears as an elongated horseshoe-shaped member of a shape and size to correspond to the shape and size of the creasing block 57, and surrounding the block for slidable engagement thereon. The blade member 70 may be conveniently attached to the pressure plate 66 by screws 74. The wall 71 is beveled at 75 to form a wedge, the purpose of which will become apparent.

In installation, the pressure plate 66, to which the blade member 70 is attached, slidably engages the dowels 35 and 36. It will be noted that the pressure plate 66 has holes 80, 81, 82, 83, 84 and 85 corresponding to the diameters of dowels 37 through 42 to permit passage of said dowels through said holes. Thus, the dowels 37 through 42, rather than inhibiting the movement of the press plate 66 along the dowels 35 and 36, provide steadying and guiding means during that movement.

The creasing block 57 is mounted outside or below the blade member 70. Thus, it can be seen that, since the creasing member 57 is attached to the dowels 37 through 42, the creasing member 57 defines one limit of movement of the blade member 70 and press plate 66. That is to say, the press plate 66 may slide upon dowels 35 and 36 (guided by dowels 37 through 42) with its lower limit of movement determined by that position at which the blade member 70 engages the creasing block 57. It will be noted that the beveled edge 75 of the blade member 70 extends below the creasing block 57, the purpose for which will appear.

Continuously urging the press plate 66 downwardly against the limits defined by the creasing block 57 are a plurality of compression springs. Thus the pair of dowels 35, the dowels 36, and 37 through 42 are respectively surrounded by coil springs 88, 89, 90, 91, 92, 93, 94 and 95. Also in compression, and therefore urging the press plate 66 in a downward direction, are a plurality of auxiliary springs illustrated as spiral leaf springs 96, 97, 98, 99 and 100. The springs 96 through 100 may be attached to the support plate 31 and the pressure plate 66 in any convenient manner such as by press fit in appropriately sized holes 101 and 162. The plurality of compression springs described provide uniform pressure upon the pressure plate'66 tending to urge that plate downwardly as far as possible, with the limit provided by its abutment against the creasing block 57. It can be readily seen that a compression applied to the support plate 31 and the pressure plate 66 will compress the plurality of springs as the plates are moved toward each other. During this movement of the pressure plate 66, the creasing block 57, being maintained in one position by the dowels 37 through 42, will extend below the blade member 70 a distance determined by the amount of pressure exerted against the force of the compression springs.

Attached to the pressure plate 66 are a plurality of short, fixed dowels 103, 104, 105, 106 and 107. The function of the dowels 103 through 107 in conjunction with the cooperating mold will be described hereafter.

The die or mold assembly, designated generally at 120, is formed of two rectangular blocks 121 and 122, that are attached together by press-fitted pins. A bottom plate 123 is removably attached to the bottom block 122, by screws 124.

The upper rectangular block 121 has a hole 126 therethrough of a shape and size corresponding to that of the work pieces in final form, which is slightly larger than the size of the smaller work piece. The top of the block 121 has a fixed gauge plate 127 attached to it by removable screws 128 (FIG. 7). The gauge 127 has a gauging edge here shown in the preferred form of a hole 129 having the shape of the larger work piece that is adapted to be folded over.

A removable gauge plate 130 is hinged at 131 to the upper block 121 so that it can be swung over or away from the block. As illustrated, the gauge plate 130 covers the top of the die, and has an overhang 132 by which it may be lifted away from the die. The gauge plate has a gauging edge, here shown in the preferred form of a hole 133 that has the shape of the smaller work piece. When swung over the die, the hole 133 is centered over the platform 141 and the fixed gauge hole 129.

A platform assembly is mounted for vertical movement in the die or block 120. That assembly includes a platform 141 shaped like the hole 136, and mounted on three dowels 142, 143 and 144 that project downwardly and are slidably received in holes 151, 152 and 153 in the lower block 122. These holes may also extend through the bottom plate 123. The middle dowel 143 has an arcuate notch 146 which functions as one element of a latching means to be more fully described. The holes 151, 152, and 153 in the base plate 122 that receive the three dowels 142, 143 and 144, are enlarged in their lower portions, as shown in FIG. 10, providing shoulders 154, 155 and 156. Lock Washers 160, 161 and 162 are attached to the bottoms of the dowels 142, 143 and 144, respectively, by screws 163, 164 and 165. The lock washers 160, 161 and 162, being of a larger diameter than the holes 157, 158 and 159, limit the upper vertical movement of the dowels 142, 143, 144 and therefore of the platform 141, by their engagement with the shoulders 163, 164 and 165.

Compression springs 166, 167 and 168 are mounted in holes 169, 170 and 171 through the lower rectangular block 122, and act between the bottom plate 123 and the platform 141 yieldingly to urge the platform 141 vertically upward to the limits defined by the engagement of the lock Washers 163-165 with the shoulders 154456.

The latching means before referred to comprises the notch 146 and the dowel 143 and a horizontally reciprocable shaft 175. The shaft 175 slidably extends through a horizontal hole 176 through the lower rectangular block 122. A removable threaded plug 178 closes the front end of the hole 176. A compression spring 179 extends between the plug 178 and the shaft 175 to continuously urge that shaft toward the rear face of the lower rectangular block 122. A pin 180 extends vertically through the shaft 175 andis reciprocably movable in a passage 181 in the lower rectangular block 122 to define the limits of movement of the shaft 175.

The shaft 175 lies alongside and in transverse, intersecting relationship to the middle platform dowel 143. The shaft 175 has an arcuate notch 183 in the side thereof adjacent to the dowel. As can be seen from the drawings (FIGS. 22, 24), the radius of the notch 183 is substantially the same as the radius of the dowel 143, while the notch 146 has a similar relation to the shaft 175. Thus, if the shaft 175 is in the left or inward position of FIGURES 21 and 22, the notch 183 receives the dowel 143, and the dowel 143 is free to move vertically, thereby permitting vertical movement of the platform 141. On the other hand, if the platform 141 is caused to move downwardly, so that the notch 146 of the dowel 143 receives the shaft 175, the shaft 175 can be moved toward the rear by the compression spring 179. In this position, the shaft 175 will act as a latch in conjunction with the notch 146 on the dowel 143 to latch the platform 141 in its lowered position. The compression spring 179 tends to maintain the shaft in its latching position.

A curved latch release actuator 185 is attached to and pivots with the movable gauge plate 130 about the hinge 131 as before mentioned. The latch release actuator has been so designed that when the gauge plate 130 is rotated away from the mold assembly, the end of the latch release actuator 185 may engage the end of the shaft 175, to move the shaft 175 toward the front of the lower rectangular block 122 and release the platform latch, so that the platform 141 again returns to its upper position.

As will appear, the folding die is operated by co-action of the plunger elements onto the die assembly. The die assembly 120 has provisions to receive, in particular ways, the projecting elements of the plunger assembly.

The principal plunger element, the compound plunger 57, 70, corresponds in position and shape to the platform 141, and can pass through the two die plate openings 133 and 128 to meet the platform.

The main dowel pins 35, 35 and 36 can slidably fit into guide holes 199, 199 and 191, in the blocks 120, 121, so that proper alignment and stability is given to the plunger and die elements during operation. Corresponding holes 190a, 190a, 191a in the fixed gauge plate 127, and 190b, 19012, and 191b in the movable gauge plate 130, permit the downward movement of the dowels at all times.

The short fixed dowels 103-107 depending from the bottom of the pressure plate 66 have a diflerent accommodation in the die assembly. There are holes 193, 194, 195, 196 and 197 in the block 120, to receive these dowels, and corresponding holes 193a197a in the fixed gauge plate 127 to receive them. However, there are no holes in the movable gauge plate 130 to receive them. The effect of this will appear hereafter.

Operation For illustration, the machine has been shown as adapted to fold together two pieces of material 200 and 205 of the shapes shown in FIGURES 12 and 13. These shapes may, of course, be modified according to the needs of desires of the operator. Also, it will be apparent that the machine may be used for a simple folding or folding and pressing operation comprising a single fold of a single piece, and various combinations thereof, and of the two or more pieces.

In the illustration the piece of material 2110 shown in FIGURE 13 is larger than the piece 265 shown in FIG- URE 12. The illustrative operation will explain how the margin of the larger piece 2641 is folded over and pressed against the underside of the smaller piece 2115. The completed product is shown in FIGURE 14. The piece 201} may typically be of leather or plastic or similar material, and the piece 205 may be of filler or stiffener material. The work illustrated is a strap for a womans shoe.

In the operation, the apparatus is placed in a press or like machine. Typically, the block or die assembly is fastened on the bed plate of the press, and the plunger assembly is attached to the press ram as by the pins 32, in known manner. With the ram elevated, the mold is loaded with the work pieces 200 and 205. To do this, the movable gauge plate is swung away from the rectangular blocks 121 and 122. The large piece 200 is located on top of the upper rectangular block 121 and the platform 141 by being fitted within the positioning gauge hole 128 of the fixed gauge plate 127.

The piece 200 in place, the top plate 130 is replaced over the mold assembly 119. Since the hole 133 in the top plate 136 is of the same size as the smaller piece 205, that hole provides a gauge for the placement of the small piece 205 onto the mold. In proper position, the piece 205 will rest upon the piece 200 just above the platform 141.

For the initial folding or creasing step, the platform 141 is in its raised position, its latch having been released. The top plate 130 is swung over the upper rectangular block 121, as illustrated in FIGURE 6. The press ram is then brought down, lowering the plunger assembly 30 into contact with the mold assembly 120. The dowels 35 and 36 will coincide with the holes 190, 191, 190a, 191a, 19Gb and 191b, in the die base, and the two gauge plates. However, as shown in FIGURES 21 and 23, since the removable gauge 130 is resting upon the mold assembly 129, the dowels 103 through 107 are prohibited from descent into the mold blocks, owing to absence of holes through the movable gauge 130 to recover these fixed dowels. They engage the top of the gauge plate 130, and thereby prevent the pressure plate 66 from moving in a downward direction. Since the pressure plate 66 is retained, of course the blade member 70 is likewise retained from movement downward.

Continued descent of the press ram forces the mounting plate 31 and the creasing block 57 downward, and accordingly compresses the springs 93 through 1011 as the pressure plate 66 is held against movement, as shown in FIGURE 23. As the creasing block 57 moves downwardly, it projects below the blade member 711 and extends into contact with the upper work piece 205 upon the platform 141. Further force upon the support plate 31 will urge the creasing block 57 downward now also forcing the two work pieces 200 and 205 and the platform 141. As the piece 209 moves downwardly within the hole 126 in the upper rectangular block 121, its edges are caught by the walls of that hole since the piece 200 is larger than the hole 126, as shown in FIGURE 15. Thus the edges of the piece 200 tend to fold upwardly as the creasing block 57 forces the pieces 2110 and 205 downwardly with the platform 141, to a point shown best in FIGURE 16.

The motion of the creasing block 57 and the platform 141 continues to carry the pieces 200 and 2115 downwardly until the notch 146 on the dowel 143 carried by the platform 141 reaches the shaft illustrated in FIG- URE 23. When the shaft 175 is thereby freed to be moved toward the back of the lower rectangular block 122 by the compression spring 179, the notch 183 on the shaft 175 is carried away from the dowel 143, and the shaft 175 will latch within the notch 146 on the dowel 143. This condition latches the platform 141 at its lower position, with the pieces 200 and 2115 retained in the positions shown in FIGURE 17, wherein the edges of the piece 200 are upstanding as shown. The ram can then be raised, withdrawing the plunger assembly 30, leaving the pieces 200 and 2115 in the position shown in FIGURE 17. When the press assembly 30 has been raised free of the mold assembly 120, the initial step is completed.

For the step of folding and pressing the margin of the piece 260 about the piece 205, the movable gauge plate 136 is lifted about its hinge 131 away from the mold assembly 1211. This, of course, exposes the additional holes 193, 193a through 197, 197a corresponding to the dowels 103 through 107 of the press assembly 30.

With the top plate 130 away from the mold assembly 120, the ram and the press assembly 30 are again lowered toward the mold assembly 120. With all of the dowels of the press assembly 30 entering appropriate holes in the mold assembly 120, the pressure plate 66 is not prevented from descending toward the upper rectangular block 121, as illustrated in FIGURE 25. Hence, the blade member 70 can now descend, and it enters the hole 126.

When the blade member 70 reaches the folded edge portion of the piece 200, the beveled edge 75 of the blade scrapes behind the upstanding edges of the piece 200, and, as shown in FIGURE 18, forces the edge away from the wall of the hole 136; With continued downward movement of the press assembly 30, the blade member 70 bottoms against the platform 141, its tapered scraping blade edge 75 having deflected the margin of the piece 200 inward to overlie the upper margin of the piece 205.

After the blade 70 thus completes its descent and is stopped, further descent of the press ram causes the creasing block 57 to be moved against the compression of the springs 90 and 95 downwardly, so that it emerges from the blade 70 once again. It engages the overturned edges of the piece 290 and firmly presses them against the margin of the piece 205, as shown in FIGURE 18. Where the margins of the larger piece 200 had been previously coated with adhesive 207, the final press action firmly cements the margin of the larger piece 200 to the upper surface of the smaller piece 205.

When the ram is then raised, withdrawing the plunger assembly 40, the top plate 120 will then be pressed at its outer end so that the latch release actuator 185 presses against the shaft 175. With increased pressure the shaft 175 will be forced toward the front of the rectangular block 122 until the notch 183 in the shaft 175 reaches the dowel 143 on the platform 141. At this position, the shaft 175 will release the dowel 143 so that the springs 166, 167 and 168 may force the platform upwardly to its initial position flush with the top of the block 121. This ejects the completed work from the machine and the block 121. The mold is then ready to be loaded with two new pieces of material 200 and 205 for a new folding operation.

It will, of course, be understood that the foregoing description is intended to be illustrative only and that the scope of the invention is to be determined only by the definition of the claims which follow.

What is claimed is:

1. In a device of the kind described: a mold assembly for receiving work material upon which a creasing and folding operation is to be performed; and a press assembly cooperative with said mold assembly for applying said creasing and folding operation; said mold assembly including a platform reciprocable vertically within a passage in said mold assembly between an unlatched position and a latched position; means for latching the platform in the latched position, the shape of said work dictating the shape of said platform defining the shape of said passage, said mold assembly when in said unlatched position being in condition for a creasing operation and in said latched position for a pressing operation; said press assembly including means for performing a creasing operation when said mold assembly is in its creasing condition and a pressing operation when said mold assembly is in its pressing condition; means for blocking the creasing and pressing means from performing a pressing operation when said mold assembly is in its creasing condition.

2. The device of claim 1 in which the means for performing a creasing operation and a pressing operation comprises a creasing block and a blade member within which said creasing block is reciprocable; said blade member at its perimeter conforming in shape to the shape of 2: said platform so that said blade member may move within said passage when said mold assembly is in its pressing condition.

3. The device of claim 2 in which the mold assembly includes a plate having therethrough a hole of the size of said platform; said plate being movable to a position whereby said hole is over said platform; said plate blocking said blade member from moving within said passage when said plate is in said last mentioned position.

4. The device of claim 3 in which said mold assembly includes latching means to place said platform in said latched position; said platform including means cooperative with said latching means for holding said latching means inoperative during a creasing operation until the termination thereof and means for releasing said latching means to place said platform in said latched position upon the termination of said creasing operation.

5. The device of claim 4 in which said plate includes means for releasing said platform from said latched position.

6. In a device of the kind described: a creasing block and a blade member; said creasing block having walls terminating in a creasing surface; said blade member substantially circumscribing said creasing block in a manner so as to provide an opening conforming in shape to the shape of said creasing surface; whereby said creasing block is slidable from a position within said blade member through said opening to a position therewithout; said blade member being beveled at said opening so as to denfine a gradually converging lip from a knife edge beyond said creasing block when said block is within said blade member to a surface adjacent said creasing block; first means movable to a first position for causing the extension of said creasing block without said blade mem her to apply a crease to material about the border thereof thereby creating a center and a border; second means for holding said crease and therewith said center and said border; said first means being movable to a second position whereby said creasing block is caused to remain within said blade member while said blade member at said beveled opening thereof forces said border inwardly; and third means causing said creasing block to move toward said opening to press a fold in said material.

7. In a device for folding material: a mold having a loading surface; a platform having a surface defining a portion of said loading surface when said platform is in a first position; said portion defined being of a shape conforming to the shape of material folded by the device; said mold including a passage communicating with said portion; said platform being normally biased to said first position and being movable to a second position within said passage and away from said loading surface; latching means movable between a platform latching position when said platform is in said second position and an unlatching position when said platform is in said first position; means for moving said platform from said first to said second position; and means for releasing the platform from said latching means to return to said first position.

8. In a device of the kind described: first means for retaining in a flat condition work material upon which a fold is to be placed; second means operable a first time for moving said first means from retaining said material in said flat condition; said second means causing said material to maintain contact with said first means; third means for changing said material from said flat condition to a creased condition and for maintaining said material in said creased condition while said second means is moving said first means; fourth means cooperating with said first means for holding said third means in said maintaining condition while said second means is rendered inoperative; said second means being operable a second time to engage said material from said third means and to force a fold in said material.

9. The device of claim 8 wherein only a portion of said first means is moved by said second means.

10. The device of claim 8 wherein said fourth means comprises latching means for latching said first means in said holding condition.

11. The device of claim 10 wherein said first means includes a movable platform flush with an adjacent surface, said third means comprises a passage of the general shape of said platform, and said platform when moved by said second means is moved through said passage to a holding position and there latched by said latching means.

12. A folding machine as described comprising a rigid block having a fiat portion, a recess in the fiat portion smaller than the area of the material to be folded and surrounded by wall means substantially perpendicular to the mouth of the recess, a platform movable from within the recess to a position for receiving the material and adjacent the mouth of the recess at which latter position a substantially planar, solid surface is defined at the flat portion, means biasing the platform toward its position adjacent the mouth of the recess, creasing means for pressing against the top of the material and maintaining contact with the material while moving the platform with the material toward the interior of the recess, the creasing means being smaller than the recess to allow the edges of the material to extend between the side walls 10 of the recess and the creasing means when the material is moved within the recess, and means for latching the platform within the recess.

13. In a device of the kind described: a first-means for retaining in a flat condition work material upon which a fold is to be placed; second means operable a first time for moving said material from said retaining means; third means for changing said material from said flat condition to a creased condition and for maintaining said material in said creased condition while said second means is moving said material; said second means being operable a second time to engage said material from said third means and to force a fold in said material, the third means comprising a passage and the second means comprising a press movable within the passage.

References Cited in the file of this patent UNITED STATES PATENTS 1,745,775 Tarbox a Feb. 4, 1930 1,941,106 Park Dec. 26, 1933 2,253,446 Spiess Aug. 19, 1941 2,680,612 Hwbelmeyer June 8, 1954 2,725,228 SeWa-rd Nov. 29, 1955 2,756,805 Silverman July 31, 1956 

